package com.ruoyi.common.utils;



import lombok.extern.slf4j.Slf4j;

import jakarta.servlet.http.HttpServletResponse;
import java.io.*;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLEncoder;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

/**
 * @ClassName ZipUtils
 * @Description zip工具类
 * @Author Alex
 * @Date 2023/4/23 下午8:55
 * @Version 1.0
 */
@Slf4j
public class ZipUtils {

    /**
     * 通过url下载zip
     * @param response 响应流
     * @param urls url文件路径集合
     * @param zipName xxx.zip
     */
    public static void urlDownloadToZip(HttpServletResponse response, List<String> urls, String zipName) {
        try {
            ByteArrayOutputStream bos = new ByteArrayOutputStream();
            ZipOutputStream zos = new ZipOutputStream(bos);
            for (String oneFile : urls) {
                byte[] bytes = getFileFromURL(oneFile);
                zos.putNextEntry(new ZipEntry(parseFileName(oneFile)));
                zos.write(bytes, 0, bytes.length);
                zos.closeEntry();
            }
            zos.close();
            response.setContentType("application/octet-stream");
            response.setHeader("Content-Disposition", "attachment;fileName=" + URLEncoder.encode(zipName, "UTF-8"));
            OutputStream os = response.getOutputStream();
            os.write(bos.toByteArray());
            os.close();
        } catch (FileNotFoundException ex) {
            log.error("FileNotFoundException", ex);
        } catch (Exception ex) {
            log.error("Exception", ex);
        }
    }

    private static Pattern pattern = Pattern.compile("\\S*[?]\\S*");

    /*
     * 解析url的文件名称
     */
    private static String parseFileName(String url) {

        Matcher matcher = pattern.matcher(url);

        String[] spUrl = url.toString().split("/");
        int len = spUrl.length;
        String endUrl = spUrl[len - 1];

        if (matcher.find()) {
            String[] spEndUrl = endUrl.split("\\?");
            return spEndUrl[0].split("\\.")[0] + "." + spEndUrl[0].split("\\.")[1];
        }
        return endUrl.split("\\.")[0] + "." + endUrl.split("\\.")[1];
    }

    /**
     * 根据文件链接把文件下载下来并且转成字节码
     *
     * @param urlPath url路径
     * @return
     */
    public static byte[] getFileFromURL(String urlPath) {
        byte[] data = null;
        InputStream is = null;
        HttpURLConnection conn = null;
        try {
            URL url = new URL(urlPath);
            conn = (HttpURLConnection) url.openConnection();
            conn.setDoInput(true);
            // conn.setDoOutput(true);
//            conn.setRequestMethod("GET");
            conn.setConnectTimeout(6000);
            is = conn.getInputStream();
            if (conn.getResponseCode() == 200) {
                data = readInputStream(is);
            } else {
                data = null;
            }
        } catch (MalformedURLException e) {
            log.error("MalformedURLException", e);
        } catch (IOException e) {
            log.error("IOException", e);
        } finally {
            try {
                if (is != null) {
                    is.close();
                }
            } catch (IOException e) {
                log.error("IOException", e);
            }
            conn.disconnect();
        }
        return data;
    }


    private static byte[] readInputStream(InputStream is) {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int length = -1;
        try {
            while ((length = is.read(buffer)) != -1) {
                baos.write(buffer, 0, length);
            }
            baos.flush();
        } catch (IOException e) {
            log.error("IOException", e);
        }
        byte[] data = baos.toByteArray();
        try {
            is.close();
            baos.close();
        } catch (IOException e) {
            log.error("IOException", e);
        }
        return data;
    }
}
